If it looks like a French Bulldog, it's possible that the dog's lineage originated in Belgium from the French speaking provinces (instead of the Walloon regions).
Just a thought :)
---of course, when I now hear a claim of a "very rare" breed/strain/type, I"ve become extremely suspicious of the breeder or their education, since sometimes they do mean well, but have loads of inaccuracies in their past experiences. :( :(
toodles